Trailer hitch



J. O. DUNCAN TRAILER HITCH Feb. 20, 1951 Filed Se'pt. .s, 194? 2 Sheets-Sheet l INVENTOR. J; O..Duncan BY Mimi HTTYS J. O. DUNCAN TRAILER HITCH Feb. 20, 1951 2 Sheets-Sheet 2 Filed Sept. 6, 1947 INVENTOR.

Patented Feb. 20, 1951 licas-m. sf ptem n answ r spit-72 421,2-

z e aimss. (01. 2805-3332);

This; invent-ion relates to: and. it: is; an: object? to provide; a novel" hitch for coupling a, trailer; to a motor vehicle.

Another object of the present invention: isto provide a trailer hitch inwhich the ball: and" socket thereof are q-uickedetachable, on coupled} by; grasping and raising orlowering and release, ing; respectively; a handle arranged; with' the: trailertongue-supported socket, which handle also serves as a means to manipulatesaid tongue: when I theh-itch' is uncoupled-1 A further object of-this-dnvention is to provide a novel; spring urged mechanism; for releasably locking the -ba-llf inthe' soeket against accidental separation;

An additionaliobiect of the invention 15:13'0' pro-.. vifde= a trailer hitch, asin-thepreceding para-.-.' graph; ilr which said 'mechaniSmincludBS. a-= slidably mounted; spring urged fork iadapted' to straddle the neckof the ball"to --therebv; normally prevent retraction of" the balk from; thesocket:

additional obiect of! thisinvention is to provide a tractor hitchwhich includes a novel spring-pressed wear-plate arrangement in thesocket, operativetoprevent l'oosepla-yof the ball in the socket when the hitch'is coupldandinusa A furthenobject' of the invention is to provide a practical, conyenient and rugged trailer hitch, and one wh ch will be exceedingly effective for thez purposefor; which itis: desi ned;

These objects are accomplished}, by means qf such structuneand relative arrangement of parts as will fully appear by a perusal'of the following specification and claims.

' In the drawings:

Fig; l isa longitudinal sectional elevationof the hitch with the parts in engagement' as for userthe normal-position oftherel'ease lever-being shown in dotted lines; and itspartially raised position being shown in full lines.

.E :';-2jis, a lon t d nal sec. ana vation; f the hitch withthe l'everirr hitchr eleasaaqsitiae. and with? the Socket free f" th iba'll.

F'igji3 is a cross section on line' 3"3 of Fig.- 2.

Fig. 4 is a plan view of the locking fork, detached.

Fig. 5 is an elevation of the release lever, detached.

Referring now more particularly to the characters 'bf reference on the drawings, the hitch comprises an elongated body, indicated generally at I, which body includes a longitudinal bottom plate 2; upstanding side walls 3, integral therewith; and a downwardly opening socket 4 formed at the forward end of said body.

The socket 4 includes a front wall 5; a back wall 6; and a top wall I; the rear edge of the top wall-1 I? terminating short of the: upper edge: of theback; wall": 6', for the purpose: hereinafterdescribed;

A ball 8 isadapted toengage in the socket, 4 from below, and said ball includes a reduced? diameter neck 9; the ball being carried on an attachment'stem I llkadapted' to be secured to a mot0r-vehioleat1the rear. The-body I securestothe tongue of -atrailer-with thesocket 4' exposed" foi engagementover-the ball 8.

Within-thesocket 4'; and in front of the backwall- 6 the socket includes a spring pressed wear plate ll urged forwardly by a leaf-spring l2; such motion of-- the wearplate l l-' being guided by the provisionof atransversely; forwardly, openingwhanneh l3 at the top ofsaid wear plate; straddlingthe rear-edge portion of the top walli 1. Thus, the wear plate H can move alimited distance in-the socket; and, beingspring -urged,

maintains the ball- 8- against loose-play insaid socketwhen thehitch is in use.

The-ballt ismormally quickdetacha-bly secured" against escape from the socket 4 by meanso-f the following-mechanism:

A gene-rally flat-lockingfork" Hlrests inparton thebottom plate 2 rearward-1y of" the" back wall 6, withthe fork legs I 5 projecting forwardly through slots I-fiinsaid back; wall whereby the fork may be projected into; the lower-port on of thesocketd instraddl ng relation-to the reduceddiameter neck 9 directlybelow-the ball 8; which loaksthe-latter=inplace. Such motion of the fork I 4- is; guided bylateral guide lugs 1 which; run

longitudinal guide slots l8'in the-side walls 3'; Thereare also-dependent guide lugs [9 on the; legs [-5 which bear againstthes dewalls 3 from: the in ide, as clearly shown in Fig. 3; I It will thus beseen' that whenthe locking for-k I4 is advanced; the ball 8 cannot escape; the socket, and such forkis'norma-lly maintained in sa -a a ced eo i inea .tollp s transyersecleat; 29= upstands; from; the rear;

of= thelocking,"for);- l4, and a plunger-rod" 21' (5 is fixed to such cleat and projects rearwardly in slidable relation through an upstanding bracket 22 fixed on the bottom plate 2; there being a heavy-duty, loaded compression spring 23 surrounding the rod 2| between the cleat 2|] and bracket 22. With this arrangement, the spring 23 normally acts to advance the locking fork; such advance motionl-being limited by an upstanding stop 24 on the fork adapted to abut the back wall 6 when the fork legs I 5 are in ball securing position.

A release lever 25 extends lengthwise of the device, being formedintermediate its ends with a transverse bearing sleeve 26 having a bore through which a cross pin 21 extends in looseplay relation; said lever extending, in its normal position, mainly rearwardly from the cross pin 21. At its normally rear end the release lever 25 includes a transverse handle 28, while at the opposite end the lever includes a rounded foot 29 positioned to engage the cleat from the front thereof.

To disengage or uncouple the hitch, it is only necessary to grasp the handle 28 and lift upwardly in a direction tending to raise the tongue of the trailer. This lifting motion results, automatically, in uncoupling of the hitch, for the reason that the handle moves from its dottedline position of Fig. 1 to the full-line position of Fig. 2. When this occurs, the foot 29 moves rear-.

wardly, shifting the cleat 2B and the fork [4 in arearward direction to release the ball 8, whereupon the socket 4 escapes the latter. Thereafter, with the socket 4 clear of the ball the handle 28 may be used to manipulate the trailer tongue to any desired, point, and to then lower said tongue into ground engagement.

To couple the hitch the procedure is merely reversed. The handle 28 is raised, the socket 4 is engaged over the ball 8, and then said handle is merely released from the hand; the loaded spring 23 then urging the fork l4 forwardly, automatically, to engage below the ball 8 to lock it in said socket.

In short, uncoupling of the hitch is accomplished solely by raising of the handle 28, while coupling of the hitch is attained by releasing said handle, when in its raised position, and with the ball and socket engaged.

"The cross pin 21 has the loose-play relation in the transverse bearing sleeve 26 so that the release lever may occupy a very low normal position lengthwise of the device, and yet act as above described.

The body l is fitted, from the socket to its rear end, with a protective hood 30 slotted lengthwise, as at 31, to permit of the necessary motion of the release lever 25.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention. as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims. :Haviug thus described the invention, the following is claimed as new and useful, and upon which Letters Patent are desired:

1. A trailer hitch comprising an elongated body which includes a bottom plate, upstanding side walls and a downwardly opening socket at-its forward end, such socket including a front wall and a back wall, the latter upstanding from the bottom plate of the body, a ball adapted to engage in the socket and having a reduced diameter neck, a locking fork slidably mounted on the bottom plate of the body, the prongs of the fork projecting through the back wall of the socket for engagement under the ball and straddling about said neck, an upstanding sto on the fork engageable with the back Wall Of the socket to limit the movement of the fork, yieldable means normally holding the stop against said back wall of the socket, a transverse upstanding cleat on the fork spaced rearwardly from the stop, a lever fulcrumed on the body, and a projecting foot on the lever normally projecting free between the stop and cleat and engageable with the cleat upon operation of the lever to move the fork against the resistance of the said yieldable means.

2. A trailer hitch comprising an elongated body which includes a bottom plate. upstanding side walls and a downwardly opening socket at its forward end, such socket including a front wall, a rear wall and a top wall extending from the front wall and terminating short of the rearwall, a ball adapted to engage in the socket and having a reduced diameter neck, a locking fork slidably mounted on the bottom plate of the body, the prongs of the fork projecting through the rear wall of the socket for engagement under the ball and straddling about said neck, an upstanding stop on the fork engageable with the rear wall of the socket to limit the movement of the fork, yieldable means normally holding the stop against said rear wall of the socket, manually operated means mounted on the body and and yieldable means between the rear wall and I Number the wear plate.

JOHN O. DUNCAN;

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date 1,450,665 Crozier Apr. 3, 1923 1,636,295 Dempsey July 19, 1927 2,078,851 Hovey Apr. 27, 1937 2,130,100 Rasmussen Sept. 13, 1938 FOREIGN PATENTS Number Country Date .,.459,39.4 Great Britain Jan. 7, 1937 816,286

" France Aug. 4, 1937 

